PORTLAND, Ore. (AP) -- Two men killed by an explosion inside a World War II-era tank at an Oregon firing range were participating in a video shoot in a military vehicle owned by one of the victims, a collector who had been filmed for shows on the Discovery Channel, the Smithsonian Channel and a video game commercial.
A crew was filming the tank firing rounds when the blast occurred Tuesday east of the city of Bend, killing vehicle owner Steven Todd Preston, 51, and Austin Tyler Lee, 22, Deschutes County Sheriff L. Shane Nelson said.
Nelson said Wednesday that the cause of the blast was under investigation and the video was to be used for an exhibit, but did not give further details. Steve Greenberg, a close friend of Preston's and fellow tank owner, said his friend had fired rounds before and "everything worked fine."
He said they were "testing some armor plate" when the explosion occurred. Preston was very safety-conscious, which is why the accident is even more shocking, Greenberg said.
Preston's close friends said he was a military vehicle collector who owned the tank as well as a World War II amphibious vehicle, a Humvee, a military motorcycle and a vintage observation plane.
"His passion was with the tank and with World War II history and collecting memorabilia," said Dennis Ripp, president of the Military Vehicle Collectors Club of Oregon. Preston was the former president of the group and was a board member of the national Military Vehicle Preservation Association, Ripp said.
"I've been broken up all day about his death," said Ripp, another close friend.
Paramedics tried to save the men, but they died from their injuries.
The armored vehicle is a 1944 M18 Hellcat, which is technically a tank destroyer, the sheriff said. Preston's friends said he took it to parades, fundraisers, auctions and live history displays at schools.
"People would donate money and he'd give them tank rides," Ripp said. "He was a great guy, a super guy. He could help anyone with projects."
Greenberg said Preston bought the tank - a surplus vehicle - from a dealer in Denver, who had imported it from Yugoslavia.
"It was in a rough shape and Steve did a beautiful job restoring it," Greenberg said. "He spent years hunting around to buy original parts, knick-knacks like binoculars, flashlights, all the tools."
Greenberg said Preston has friends around the world, because he traveled to other countries looking for vehicle parts. He also said Preston was licensed by the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives to fire live ammunition from the tank.
Greenberg said they and their tanks took part in a commercial for the video game "World of Tanks" that was shot last week.
In 2011, the Discovery Channel filmed Preston for a reality series. And he took part in the Smithsonian Channel series "The Weapons Hunter," focused on rare military artifacts, that is due to air next month.
Preston and another friend had started a nonprofit and planned to build a museum to display the historic vehicles, Greenberg said.
He said Preston, who owned a Portland towing company, leaves behind a wife and two children.
"He was generous, caring, he was there for other people. It breaks my heart that he is gone," Greenberg said.